1. Field of the Invention
The invention relates to a device for compacting road paving materials.
2. Background
Such a device is known from DE 26 00 108 A1. According to this document, a screed upstream of which is arranged a tamper for precompacting the paving material is fastened to the road finisher. During the beginning of a paving operation, it thus occurs that the bituminous mixture in the warm state remains sticking on the cold tamper strip. However, the mixture sticking on the tamper strip leaves behind grooves in the surfacing which can no longer be removed by the following screed and therefore remain on the surface of the roadway covering. To avoid these grooves at the beginning of a paving operation, it is known to heat the tamper strip. The use of a gas burner has been replaced here by an electrical heater which is inserted into an open or closed hollow profile which forms the tamper strip. The electrical heater is then situated in the interior of the tamper strip.
EP 0 641 887 B1 discloses a road finisher and tool in the form of a tamper strip for a paving screed. The tamper strip forms a channel between a carrier part and a wear part, in which channel a heating element, in particular a heating bar, is provided. The heating element is an electrical flat-tube heating body which is screened upwardly by a shim. Here, the shim ensures that the heating element is securely clamped such that as large a contact surface as possible results for heat conduction. A disadvantage here is that the heating element frequently breaks. The replacement of a defective heating element leads to undesired downtimes of the road finisher. The maintenance requirement is increased. The heating capacity is further determined by the contact heat.